Outboard motor



y D. R. CLARKE 2,207,372

OUTBOARD MOTOR Filed June 5, 1936 2 Sheets-Sheet 1 Y 1 RNEYJ July 9, 1940.

R. CLARKE OUTBOARD MOTOR Filed June 5, 19:6 2 Shets-Sheet 2 0 FRfLAR/(i 47 72,

Patented July 9, 1940 UNITED STATES PATENT OFFICE OUTBOARD MOTOR Douglas Rolph Clarke, Toronto, Ontario, Canada Application June 5, 1936, Serial No. 83,745 8 Claims. (01. 11518) My invention relates to improvements in outboard motors, and the object'of the invention is to devise an outboard motor which will be very compact and rigid, in which there will be no weaving action between the component parts thus eliminating power loss and repair costs commonly incurred, in which the cranking operation, the starting and warming up of the motor can be performed when the propeller isclear of the water and, therefore, requiring less effort to crank the driving motor and thereby rendering starting easier due to the absence of resistance of water to the propeller, in which better protection against damage is provided for the propeller when striking an obstruction and the use of shear pins which are diflicult to replace eliminated, in which the use of gears to transfer power from a crank shaft to a. propeller shaft-is eliminated also eliminating the gear noise and reducing the consumption of the power generated, in which'the suction of water into the engine through the exhaust is eliminated during the starting period, in which the carburetor is mounted above the fuel level thereby eliminating danger of fuel flooding the engine, in which the spark plug is cooled by the iii-coming stream of fuel mixture passing over the spark plug boss and at the same time breaking up the heavy unvaporized particles of fuel by impinging them on the comparatively hot boss to form a more homogeneous mixture'and producing a better engine performance especially at slow speeds, in which the cylinder and combustion chamber walls are cooled'by direct contact with the water in which the propeller operates thereby eliminating extra water jacketing walls saving weight and cost of manufacture, it consists essentially of the arrangement and construction of parts all as hereinafter-more particularly explained.

i Fig. 1 is a side elevation of my outboard motor showing it attached to a portion of a boat stern.

' Fig. 2 is a vertical section through Fig. 1.

Fig. 3 is a plan section, the section being taken through the upper portion of the carburetor casing. I

Fig. 4 is a sectional view on line 4+4 Fig. 2. Fig. 5 is a sectional view on line 5-5 Fig. 2. Fig. 6 is a sectional view on line 6--6 Fig. 2. Fig. 7 is a sectional View on line l--l Fig. 2. I Fig. 8 is a sectional view on line 8-8 Fig. 2.

Fig. 9 is a side elevation of the distributing mechanism showing the drive shaft in section.

Fig. 10 is an enlarged fragmentary detail of the distributing mechanism as illustrated in In the drawings like letters of reference indicate corresponding parts in each figure.

I indicates the fuel tank. 2 is an engine block provided at its upper end with a flange 3 secured by bolts 4 to the bottom wall of the-fuel tank I. i5 5 is flange extending from the lower end of the engine block 2. 6 isa propeller carrying body whichis connected to the flange 5 by means of bolts i. By this means the fuel tank, engineblock, and propeller carrying body are rigidly l6 connected together to form'a, single unit.

l is a clamping bracket provided with an arm 8 having an internally threaded boss 9, through which a threaded clamping screw l0 extends, the inner end of the screw being provided with a 15 head H engaging the stern portion l2 of'the boat, the head ll being forced intoposition to clamp such portion by means of a handle l3. M is a short shaft extending through the side flanges of the bracket 1'. p I v 20 i5 is a vertical shaft preferably tubular which is secured in lugs l6 and I! extending from the rear wall ofthe fuel tank I.' l8"is 'a member provided with lugs l9 and 20 ,through which the vertical shaft l5extends and in which the shaft 25 is turnably held so that the outboard'motor can be swung either to one, side or the other'forthe purpose of steering. I I i 2i isa lug extending upwardly from the top I wall ofthe fuel tank I provided with an orifice 3o so that the outboard motor may be swung by the 35 steersman to either one side or the other.

The member I8 is also provided with 9. lug 25 of sleeve form having an orifice 26 through which 7 the short shaft l4 freely extends permitting the outboard motor to be swung upwardly thereon on a vertical plane when manipulated by thehandle -24. 21 is a cam member provided'with anotch 28 in its periphery. The" cam member 2! is securedor formed integral with the lug 25 so as to swing therewith when the outboard motor is 4 swung in" a vertical plane.

29 is a pin which is pivoted at 30 to the'bracket l, the free end of the pin extending through a, slot 3 1- formed in the opposite wall ofthe bracket 1'. The pin 29 is held in its raised position by 50 means of a spiral spring 32. v I I When the outboard motor is swung to the "raised position by depressing the handle 24, the cam member 21 is carried into engagement with the pin 29;forcing it downwardly against the tension of the spring 32 until the notch 28 is reached. The pin 29 is immediately carried into such notch by means of the spring 32 looking the outboard motor in the raised. position. As shown in Fig. 3 the pin 29 protrudes beyond the bracket 7 at its free end so that when it is desired to release the outboard motor all it is necessary to do is to grasp the projecting portion of the pin and force it downward in the slot 3! out of engagement with the notch 28 thereby freeing the outboard motor so that it will swing downwardly to its normal position.

33 is the engine cylinder formed in the engine block 2, 36 being the inlet port and 35 the exhaust port. 36 is a carburetor of suction type enclosed in a casing 31. I do not describe this carburetor in detail as it is of a type commonly in use. 38 is a feed pipe by which the fuelis drawn up from the fuel tank into the carburetor. 39 is the inlet manifold extending from the carburetor vertically through the fuel tank and connected at its lower end to a duct 46 leading to the inlet port 36.

6! is an igniter plug which is mounted in a hollow boss 42 which extends transversely of the duct 43 so as topermit the vaporized fuelfrom the carburetor passing around each side of the boss as clearly indicated in Fig. 8 serving to keep it comparatively cool. 43 is duct leading from the exhaust port 35 of the cylinder 33. In the upper end of the duct M is screwed a coupling member 45 in which is secured a vertical tube 46 extending upwardly therefrom to a point above the water level.

4'! is a tubularhoodwhich extends. over the open upper end of the exhaust tube 66 and is secured in a stationary position by means of the straps 48 and d9 secured at 56 and 5! in the recessed wall of, the fuel tank l. The lower end of the tubular hood extends below the water level so the exhaust gases from the exhaust port 35 of the engine are passed into the water.

52 is the piston of the engine operating within the cylinder 36 and. provided with a piston rod 53. 6 is the propeller carrying body, the outer surface of which is appropriately streamlined to pass easily through the water. 5 is the crank shaft of the motor journalled in bearings ES-and 56. The inner end of the crankshaft 56 is provided with a crank disc 61' having a crank pin 58 pivotally connected to the lower end of the piston rod 53. The outer end of the crank shaft 54 is provided with a tapered portion 59 on to which is driven a cylindrical boss 66.

BI is a sleeve. 1 62 are the propeller blades which are formed integral with the sleeve 6|. The sleeve 61 fits around the boss 66 against an annular rib 64. are orifices formed. in the eriphery of the boss 66 and 66 are recesses formed in the inner'periphery of the sleeve 6| and normally located in radial alignment with the orifices 65. 68 are spiral springs inserted in the orificesfifi and bearing against locking balls 69 which normally fit in the recesses 66. Normally the pressure of the springs 68 is sufficient to hold the balls 69 in engagement with the recesses 66 to form a driving engagement between the sleeve 6| and the boss 66.

Should one ofthe blades, however, strike an obstruction exerting an abnormal pressure against such blades, the balls 69 will be forced inward out of the recesses 66'so as to permit the blades 69 and sleeve 6| turning freely around the boss, thus avoiding the breaking or damaging of the blade.

The boss 66 is locked upon the tapered porclearly indicated in Fig. 2.

tion 5 of the crank shaft by means of a lock nut 10. H is a pulley member which is secured to the outer face of the boss by means of screws 72 suitably spaced apart.

When it is desired to crank the engine, the outboard motor is swung upwardly by means of the handle 24 so that the propeller is carried clear of the water. A rope is then wound around the pulley member H and by pulling upon the rope the pulley member is revolved so as to turn the crank shaft 56 and thus crank the engine.

In order to advance or retard the spark I have provided the following mechanism which I will now describe.

it is a grooved member forming part of the packing M of the crank shaft. 15 is an annular member provided with an annular tongue 16 fitting into the groove of the member 13 so that the annular member 76 is turnable concentric with the crank shaft 56. The crank shaft 59 is provided with a cam projection Tl extending radially therefrom and adapted toengage a pivot arm 18 carried by the annular member 15 as indicated atlfi. The upper end of the arm 18 is provided with a movable contact 16 coacting with a stationary contact 86 carried by the annularmember 15. El and 82 are lugs extending from the annular member 15 at diametrically opposite sides. The lug 81 is connected by a tension spring 83 to a pin 8% extending from any suitable part of the propeller carrying member 6 as indicated 211385.

86 is a cable secured at one end to the lug 82. The cable 86 extends upwardly through the engine block as indicated in Fig. 2 and through a tubular member 87 secured at its ends in the upper and lower walls of the fuel tank I. 88 is a lug forming part of the carburetor. In the lug 88 is journallecl a shaft 89. 96 is the operating shaft of the carburetor extending upwardly through an air inlet orifice 9| through which air is supplied to the carburetor. 92 is a hooded member secured to the upper end of the shaft so as to overhang the edges of the air inlet opening 9i as to the shaft 96;. 9 is an arm bearing at its free end upon the operating surface of the cam 63 and secured at its opposite end to the shaft 89. '95 is an arm secured to the opposite end of the shaft 89, the free end of the arm being secured to the upper end of the cable 86.

By this construction it will be seen that by turning the hooded member 92 the operating shaft 96 of the carburetor is turned and at the same time the cam 93 is rotated so as to raise the cam arm 94 and thereby rock the shaft 89 raising the arm 95 so as to pull upon the cable 96 and thereby rotate the annular member 15 and the pivoted arm l8 carried thereby around the shaft 59 carrying the arm 16 towards the cam'projection Tl. By this means the spark is advanced, the cam 11 engaging the arm 78 so as to carry the contacts l9 and Bil apart.

When the hooded member 92 is turned in the opposite direction, the cam arm 94 swings down on the surface of the cam 93 so as to release the pull on the cable 86 and allow the spring 83 to operate to turn the annular member 75 in the opposite direction to carry the arm 78 away from the cam projection Ti and thereby retard the spark.

The stationary contact 86 of the distributor is connected by a wire 96 leading to one terminal of a battery 9?, the other terminal of such battery being connected by a wire 98 to the bind- 93 is a cam secured ing post 99 of the spark coil I00. The spark coil I00 is also provided with a binding post llll connected ,to the opposite terminal thereof from which a wire Hi2 leads to ground. The spark coil I00 is also connected by a high tension wire I03 to a spark plug 4! as indicated in Fig. 2.

From this description it will be seen that I have devised an outboard motor which is very compact and rigid in construction, such outboard motor consisting of three main parts namely the fuel tank, engine block and propeller carrying body which are rigidly connected together to form a single unit and thus eliminating any weaving action and wear between the component parts, in which the cranking, starting and warming up operation of the motor may be performed while the propeller is clear of the water therefore requiring less effort to crank the motor at starting eliminating the resistance due to the propeller revolving in the water, in which there is less liability for the propeller to become damaged when striking an obstruction, in which the driving gears for transferring power between a crank shaft and propeller shaft are eliminated overcoming the consequent noise and substantially seven per cent of power loss, in which the suction of the water into the engine through the exhaust is eliminated and the danger of flooding the engine with fuel by mounting the carburetor on the top of the fuel tank and in which the boss on which the spark plug is mounted is kept comparatively cool and is sufficiently hot to provide for the breaking up of hot particles of fuel impinging thereon and thereby producing greater efficiency in engine performance.

What I claim as my invention is:

1. In an outboard motor, the combination with a submersible propeller carrying body, a fuel tank and an engine block interposed between and rigidly connected to the fuel tank and propeller body, of a carburetor mounted on the fuel tank, an inlet duct extending from the carburetor through the fuel tank to the inlet port in the engine block, and a cupped igniter boss extending transversely of the inlet duct and around which the cool incoming gases flowing through the inlet duct pass.

2. In an outboard motor, the combination with the propeller carrying body, engine block and fuel tank rigidly connected together, a supporting bracket in which the tank is pivoted at its upper end and a steering arm, of a crank shaft journalled in the body, a pulley member secured to the outer end of the shaft around which a rope is adapted to be wound, and means effective upon movement of the outboard motor to its raised position preparatory to the cranking operation to automatically lock the outboard motor in said raised position.

3. In an outboard motor, a supporting bracket in which the upper end of the outboard motor is pivotally mounted to have a submerged lower end, of a normal horizontal cranking shaft journalled in the submerged portion of the outboard motor, a crank mounted on the inner end of the shaft, means for driving the shaft, means at the outer end of the shaft for cranking the engine, a handle arm for swinging the submerged lower end of the outboard motor into a cranking position above the water level, and means effective upon movement of the outboard motor to its raised position preparatory to the cranking operation to automatically lock the outboard motor in said raised position.

4. In an outboard motor, a supporting bracket in which the upper end of the outboard motor is pivotally mounted and having a submerged lower end, of a normal horizontal cranking shaft journalled in the submerged portion of the outboard motor, a propeller mounted on the outer end of the shaft, means for driving the shaft, means at the outer end of the shaft for cranking the engine, a handle arm for swinging the submerged lower end of the outboard motor into a cranking position above the water level, means for releasably locking the outboard motor in the raised position while cranking comprising a cam member secured to the pivot support of the outboard motor and provided with a peripheral notch, a spring pressed member carried in the supporting bracket depressed by engagement of the cam periphery to spring into locking engagement with the notch.

5. The combination with an outboard motor pivoted at its upper end to swing upwardly and including an internal combustion engine having a submerged exhaust, a pipe extending upwardly from the exhaust above the water level, a tubular hood extending over the open end of the exhaust pipe and extending normally at its lower end or mouth to below the water level, which mouth is adapted to rise above the water level when the outboard motor is swung to its upward position.

6. In an outboard motor, a propeller carrying body formed of a single integral unit having a central bore extending therethrough from end to end, bearings mounted in the bore, a crank shaft mounted in the bearings, a crank disc secured to one end of the shaft, a propeller secured to the opposite end of the shaft, and a closure insertable in the bore of the propeller carrying body at the opposite end thereof to the propeller.

'7. In an outboard motor, the combination with a submersible propeller carrying body, a fuel tank and an engine block interposed between and rigidly connected to the fuel tank and propeller body and containing an engine cylinder in the lower portion thereof having an inlet port and a duct leading from the top of the block to the inlet port, of a carburetor mounted on the fuel tank above the fuel level, and a tubular inlet duct extending from the carburetor through the fuel tank to the duct of the engine body leading to the inlet port of the cylinder.

8. In an outboard motor, a propeller carrying in the last named position thereof during the,

cranking operation.

DOUGLAS ROLPH CLARKE. 

